Rhodamine B
Definition
A xanthene dye (C28H31ClN2O3, MW 479.0) with brilliant pink fluorescence, listed on the EU REACH SVHC candidate list as a suspected carcinogen (H351). Not permitted in cosmetics in the EU (not in Annex IV), the US (not a listed D&C or FD&C colour), or India. Detected in lipstick samples from informal South Asian markets.
- Formula
- C28H31ClN2O3
- Molecular weight
- 479.0 g/mol
- EU hazard status
- REACH SVHC candidate, suspected carcinogen (H351)
- Regulatory status
- Not permitted in cosmetics in EU, US, or India
- Detected in
- Lipstick from informal South Asian markets
Common questions
Why does Rhodamine B still turn up in some lipstick products despite bans?+
It is cheap, chemically stable and gives an intense pink shade, which keeps it attractive to informal or unregulated manufacturers who substitute it for approved colourants, particularly in low-cost cosmetics sold outside formal retail channels.
How is Rhodamine B identified in a cosmetics lab test?+
Analysts typically use TLC, HPLC or spectrophotometry to compare retention time and absorbance against a Rhodamine B reference standard, since its fluorescence and chromatographic behaviour differ measurably from permitted colourants.
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